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Summary  

This paper suggests an international benchmarking method of disembodied knowledge flow structure. Using patent citation as a proxy measure of disembodied knowledge flow, national knowledge network is developed. Structural equivalence measure is applied to comparing the knowledge network of Korea and Taiwan with that of USA. Static and dynamic comparison make it possible to benchmark disembodied knowledge flow structure efficiently and identify  convergent and divergent industries between developing countries and USA. It is also a meso-study that could be conducive to building a comprehensive analytical framework of national innovation system.

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The aim of this research was to enhance the use of nuclear analytical techniques for air pollution studies and to study the feasibility of the use of instrumental neutron activation analysis (INAA) as a routine monitoring tool to reveal environmental pollution sources. For the collection of air particulate samples, the Gent stacked filter unit, low volume sampler with Nucleopore membrane filters were used. Trace elements in samples collected at two suburban residential sites, Taejon and Wonju city in the Republic of Korea, were analyzed by INAA. Variations of the elemental concentrations were measured monthly and the enrichment factors were calculated for the fine (<2 μm EAD) and coarse size (2–10 μm EAD) fractions. The analytical data were treated statistically to estimate the relationship between the two variables, the concentrations of elements and the total suspended particulate matter. The results were used to describe the emission source and their correlation.

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Naturally occurring radionuclides (NORN) such as 40K, 226Ra and 232Th from 44 surface sediment samples collected from four desert regions of Chinese were determined to investigate the regional characteristics of the source areas of Asian dust. The radionuclides for 41 surface sediment samples collected from seven sites of the Keum River area in Korea were also determined to compare the regional characteristics with the Chinese desert area. The specific activities (SA) and the specific activity ratios (SAR) of the radionuclides were investigated for distinguishing the source region of Asian dust. The SA of 226Ra and 232Th as well as the SAR of 226Ra/40K and 232Th/40K were found to be useful to characterize source area and tracing Asian dust.

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The complexation of Eu3+ and Am3+ ions with the humic acids has been investigated at various pH (4.0, 4.5, 5.0, 5.4) in 0.1M NaClO4 solution using solvent extraction technique. Two humic acids are used in this study: humic acid extracted from the soil of Taejon on the Okchon Basin of Korea (TJHA) and commercially available one from Aldrich Chemical Co. (AHA). The total carboxylate group concentrations were determined to be 3.58 meq/g and 4.59 meq/g for Taejon and Aldrich humic acids, respectively. The conditional stability constants (log 1 and log 2), dependent on the pH of the solution, of the complexes of Eu3+ and Am3+ ions with the humic acids have been determined at the ionic medium of 0.1M NaClO4. The values of stability constants with the degree of ionization of TJHA for Eu and Am complexes are quite well agreed with those of Lake Bradford humic acid (LBHA), indicating that structural characteristics of TJHA and LBHA may be quite similar to one another.

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. Participants were administered Structured Clinical Interview for the DSM, Fourth Edition and Korean Wechsler Adult Intelligence Scale, Fourth Edition by a clinical research psychologist to exclude those who met criteria for a lifetime Axis I psychiatric

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Summary  

The stability constants of Eu3+ and Am3+ with the site specific humic acid (YKHA) have been determined. The humic acid has been extracted from the soil of Yongkwang area belonging geologically to the Okchon Basin of the Korean Peninsula, where the nuclear power plant is located. The total carboxylate capacity, the acidity constant (pKa), and the binding constants with Eu3+ and Am3+ have been determined for humic acid.

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Abstract  

Because R&D conducted in electronics and chemistry has made significant contributions to South Korean economic development, past strategies in technology developments in these fields are addressed. The possibility of capturing national technology strategy and policy characteristics from patent analyses is explored. For the analysis, data were analyzed from 557 US patents in electronics and 108 US patents in chemistry, registered by Korean inventors, between 1989 and 1992. Descriptive statistics of aggregated patent information were equivalently mapped to each strategy in the two fields. Industry-specific features and past technology strategies in electronics and chemistry are identified. Electronics was driven by the private sector, while chemistry was driven by the public sector. Inventors in both fields are seeking clustered innovation on which subsequent innovation can be accumulated and/or applied to numerous heterogeneous fields. Contrary to the stated assumption, many Korean electronic innovations were based on scientific outputs such as papers. Of the knowledge strategy variables, size of invention and number of heterogeneous classifications are considered to be an important factor that affects patent citation counts in both fields.

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Internet, gaming, and smartphone addiction in children and adolescents, and identify risks and protective factors. It was conducted from August 2015 to August 2019 in Seoul and Gyeonggi-do, Korea and included 194 participants ( Jo et al., 2019 ). Children

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Summary  

For the identification of air pollution sources, about 500 airborne particulate matter (PM2.5and PM10) samples were collected by using a Gent air sampler and a polycarbonate filter in an urban region in the middle of Korea from 2000 to 2003. The concentrations of 25 elements in the samples were measured by using instrumental neutron activation analysis (INAA). Receptor modeling was performed on the air monitoring data by using the positive matrix factorization (PMF2) method. According to this analysis, the existence of 6 to 10PMF factors, such as metal-alloy, oil combustion, diesel exhaust, coal combustion, gasoline exhaust, incinerator, Cu-smelter, biomass burning, sea-salt, and soil dust were identified.

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Abstract  

Aerosols and source related materials (fly ash from refuse incinerators, vehicle exhaust and soil) were collected in April, 2002 in the northern areas of Jeju-do, Korea, and the Pb isotopic ratios (207Pb/206Pb and 208Pb/206Pb) of the samples were measured in order to estimate the Pb sources of the aerosols. The Pb isotopic ratios of the aerosols were classified into two groups, depending on the sampling date. One group showed similar Pb isotopic ratios with those of the source related materials, suggesting that the contribution of the regional sources to the aerosols was very large. The other showed different Pb isotopic ratios from those of the regional sources and relatively high Pb isotopic ratios compared to the ratios of the first group. The results suggest that in the continental Asia there seems to be a long range transport of Pb with high ratios in desert sands, which are carried by northwest seasonal winds.

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